Studies on the structures of new components of leucomycin, A4(IV), A5(III), A6(VI), A7(V), A8(VIII) and A9(VII), were carried out in parallel with those on components A1(I) and A3(II), namely acetylation, and acid and alkaline hydrolysis. The pairs of components IV and III, VI and V, and VII and VIII gave respectively, acetates X, XI and XIII. Components IV, VI and VIII had then respectively, 4-O-n-butyryl-, 4-O-propionyl- and 4-O-acetyl-mycarose replacing the 4-O-isovaleryl mycarose in A3. Like A3, components IV, VI and VII had an O-acetyl group on C-3 of the 16-membered lactone. Leucomycins A4, A5, A6, A7, A8 and A9, as reported earlier, are new components of leucomycin produced by an actinomycetales, Streptomyces kitasatoensis Hata1,5). The structures of these new components were the subject of a brief communication6). The present paper presents the details for the communication plus some spectroscopic features of the degradation products of these components.